diff --git a/mivan/src/main/java/mivan/model/Loan.java b/mivan/src/main/java/mivan/model/Loan.java
index 0e2b844..5c03d4b 100644
--- a/mivan/src/main/java/mivan/model/Loan.java
+++ b/mivan/src/main/java/mivan/model/Loan.java
@@ -15,10 +15,10 @@ public class Loan {
 	private long id;
 
 	@Column(name = "date_start", nullable = false)
-	private String date_start;
+	private long date_start;
 
 	@Column(name = "date_end", nullable = false)
-	private String date_end;
+	private long date_end;
 
 	@Column(name = "state", nullable = false)
 	private String state;
@@ -35,7 +35,7 @@ public class Loan {
 	@JoinColumn(name = "user")
 	private User user;
 
-	public Loan(String date_start, String date_end, String state, Item item, Staff staff, User user) {
+	public Loan(long date_start, long date_end, String state, Item item, Staff staff, User user) {
 		this.date_start = date_start;
 		this.date_end = date_end;
 		this.state = state;
@@ -48,11 +48,11 @@ public class Loan {
 		return id;
 	}
 
-	public String getDate_start() {
+	public long getDate_start() {
 		return date_start;
 	}
 
-	public String getDate_end() {
+	public long getDate_end() {
 		return date_end;
 	}
 
@@ -76,11 +76,11 @@ public class Loan {
 		this.id = id;
 	}
 
-	public void setDate_start(String date_start) {
+	public void setDate_start(long date_start) {
 		this.date_start = date_start;
 	}
 
-	public void setDate_end(String date_end) {
+	public void setDate_end(long date_end) {
 		this.date_end = date_end;
 	}
 
diff --git a/mivan/src/test/java/mivan/LoanTest.java b/mivan/src/test/java/mivan/LoanTest.java
new file mode 100644
index 0000000..a3c2778
--- /dev/null
+++ b/mivan/src/test/java/mivan/LoanTest.java
@@ -0,0 +1,100 @@
+package mivan;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.Optional;
+
+import org.junit.jupiter.api.Order;
+import org.junit.jupiter.api.Test;
+
+import mivan.model.Item;
+import mivan.model.Loan;
+import mivan.model.Staff;
+import mivan.model.User;
+import mivan.repository.LoanRepository;
+import mivan.repository.LoanRepositoryImpl;
+
+public class LoanTest {
+
+	private LoanRepository loanRepository = new LoanRepositoryImpl();
+
+	@Test
+	@Order(1)
+	void testAddBook() {
+
+		long date_start = 1234;
+		long date_end = 2345;
+		String state = "loaning";
+		
+		Item item = null;
+		Staff staff = null;
+		User user = null;
+
+		Loan loan = new Loan(date_start, date_end, state, item, staff, user);
+
+		loanRepository.addLoan(loan);
+
+		int size = loanRepository.getSize();
+
+		assertEquals(size, 1);
+
+	}
+
+	@Test
+	@Order(2)
+	void testUpdateBook() {
+		
+		long date_start = 1234;
+		long date_end = 2345;
+		String state = "loaning";
+		
+		Item item = null;
+		Staff staff = null;
+		User user = null;
+
+		Loan loan = new Loan(date_start, date_end, state, item, staff, user);
+
+		loanRepository.addLoan(loan);
+		
+		String update_state = "returned";
+		
+		loanRepository.updateLoan(1L,update_state);
+
+		Optional<Loan> opt_loan = loanRepository.findById(1L);
+
+		Loan loan2 = opt_loan.get();
+		assertTrue(update_state.equals(loan2.getState()));
+
+	}
+
+	@Test
+	@Order(3)
+	void testDeleteBook() {
+		
+		
+		long date_start = 1234;
+		long date_end = 2345;
+		String state = "loaning";
+		
+		Item item = null;
+		Staff staff = null;
+		User user = null;
+
+		Loan loan = new Loan(date_start, date_end, state, item, staff, user);
+
+		loanRepository.addLoan(loan);
+
+		Optional<Loan> opt_loan2 = loanRepository.findById(1L);
+
+		Loan book2 = opt_loan2.get();
+		long ID = book2.getId();
+
+		int start_size = loanRepository.getSize();
+		loanRepository.deleteLoanById(ID);
+
+		int size = loanRepository.getSize();
+		
+		assertEquals(start_size, size);
+	}
+}